*{
    margin: 0px;
    padding: 0px;
}
html,body{
    height: 100%;
    width: 100%;
}
#daohang{
    width:100%;
    height:100px;
    background-color: #dff9f9;
    position: fixed;
}
li{
    float:left;
    margin-left: 20px;
}
#one{
    width: 100%;
    background-color: #7fffd4;
}
#two{
    width: 100%;
    background-color: #99b0ff;
}
#three{
    width: 100%;
    background-color: #1eb2ff;
}